1. Technical Field
The present invention relates to a test apparatus and an electronic device. More particularly, the present invention relates to a test apparatus and an electronic device which are configured in such a manner that a different test period can be selected for each test terminal.
2. Related Art
To test a device under test (DUT), a test apparatus generates a test signal for each test period, inputs the generated test signal into a terminal of the DUT, and receives an output signal from the terminal of the DUT in response to the test signal. The test apparatus then compares the received output signal with an expected value which is expected to be output from the DUT when the test signal is input into the DUT. This is how the test apparatus tests the functions of the DUT.
Here, the test period is generated by a period generator. In the test apparatus, one period generator is provided for each terminal group including, for example, 4 to 16 test terminals. In other words, the plurality of test terminals making up the terminal group corresponding to the period generator are under the control of the same test period. Unexamined Japanese Patent Application Publication No. H09-96663 discloses a period generator adopted for a test apparatus.
Here, it may be desired to use the test apparatus in order to test a device that has different periods for the input thereto and the output therefrom. For example, the test apparatus may be used to test a device that is input with a clock which has not been multiplied by a phase-locked loop and outputs data in synchronization with the clock which has been multiplied. If such is the case, a plurality of terminal groups each including a plurality of test terminals are provided in the DUT so that different test periods can be applied to the test terminals of the DUT.
However, this solution has a drawback. When only one of the test terminals constituting a terminal group is utilized, the rest of the test terminals can not be used. Furthermore, this may limit the arrangement of the remaining test terminals of the DUT. As a different solution, a period generator may be provided for each test terminal. This technique, however, increases the scale of the circuit for the test apparatus, and is therefore not a realistic solution.